This invention relates generally to a pump and, more particularly, to an oil burner pump having a regulating valve for delivering fuel to an oil burner. A pump of this general type is disclosed in Swedberg U.S. Pat. No. 3,566,901.
In such a pump, the fuel, when pressurized, forces the regulating valve open against the force of a spring which snaps the valve closed when the pump shuts off. The force exerted on the valve by the spring may be increased or decreased by turning an adjusting screw to change the compression of the spring. In the pump of the Swedberg patent, the adjusting screw is threaded into a cap fitting which, in turn, is located in a bore in the pump body. The bore for the adjusting screw is coaxial with a bore which receives the valve and which is internally threaded so as to receive the cap fitting.
In prior pumps of the above type, the inlet port which is primarily used is located in the cover of the pump. Whenever it is necessary to remove the cover to service the pump, it is necessary to first disconnect the inlet or supply line from the inlet port.
In order to avoid the need for disconnecting the inlet line, the pump of the present invention includes an inlet bore formed in the pump body and extending in closely spaced and parallel relation to the bore for the regulating valve. Because of the closely spaced relation between the inlet bore and the valve bore, difficulty has been encountered in incorporating a valve adjusting screw into the pump body.